Roasting-furnace.



G. E. DEWEY.

ROASTING FURNACE.

APPLIOATION FILED MAB.. 25, 1910.

992,407. Patented May16,1911.

3 SHEETS-SHEET 1.'

C. E. DEWEY. ROASTING FURNACE.

APPLIoATIoN FILED 1119.11.25. 1910.

Patented May16,1911.

4. www WW WW1/mous I @i o. E. DEWEY. ROASTING FURNAGE. APPLICATION FILEDMAB.. 25.A 1910.

992,407. Patented May. 16, 1911.

3 SHEETS-SHEET 3.

1 r i I CHAUNCEY E. DEWEY, 0F DENVER, COLORADO.

ROASTING-FURNCE.

Specification of Letters Patent.

Patented May 16, 1911.

Application filed March 25, 1910. Serial No. 551,578.

To all 'whom et may concern:

Be it known that I, CHAUNGEY E. DEWEY, a citizen. of the United States,residing in the city and county of Denver and State of Colorado, haveinvented certain new and useful Improvements in Roasting-Furnaces; and Ido declare the following to be a full, clear, and exact description ofthe invention, such as will enableJ others skilled in the art to whichit appert-ains to make and use the same, reference being had to theaccompanying drawings, and t-o the letters and figures of referencemarked thereon, which form a part of this specification.

My invention relates to improvements in roasting furnaces adapted forroasting ores for the purpose of removing certain impurities or elementswhich render the ore refractory and diiiicult to treat, such as sulfur,arsenic, etc.

My present improvements relate to special means for connecting therabble arms with a hollow upright shaft, whereby the said arms may bereadily connected therewith or detached therefrom as may be desired.

As shown in the drawing, the furnace consists of an upright casingequipped with shelves through which passes a hollow central shaft, uponwhich are mounted hubs to which the rabble arms are secured. This shaftis mounted to rotate and the rabble arms, which are equipped with plows,travel therewith and act upon the ore upon the shelves to stir thelatter and at the same time cause it to gradually work downwardly fromone shelf to another until it reaches the lowermost shelf where it isdischarged completely roasted. In other words, the impurities, assulfur, have been removed suficiently to permit the advantageoustreatment of the ore for the purpose of saving the precious-metal valuescontained therein.

The shelves areJ connected with and supported by the casing, and arealternately provided with openings at their inner and outer edges,whereby the ore is gradually fed from one shelf to another, the plows ofthe rabble arms being so set for instance that the ore upon theuppermost shelf is caused to travel toward the shaftand pass downwardlythrough an opening of the shelf surrounding the shaft, to the shelf neXtbelow. The plows located in the lower compartment and acting upon theore of the next shelf below, cause the material to travel oustwardlywhereby it is discharged through openings at the outer edge of theshaft, causing it to fall to the shelf next below, and so on, until theore has traveled from the top shelf to the bottom of the furnace, whereit is discharged as heretofore explained.

The hubs with which the rabble arms are connected, each consists -of twomembers suitably connected and locked upon the shaft, the latter beingprovided with shoulders forming supports for the hubs. These hubs areprovided with sockets of special construction for the reception of therabble arms, each arm being provided with a lug adapted to enter a slotor groove formed in the outer wall of the socket and terminating in a.slot extending at right angles to the first named slot, whereby bygiving the rabble arm aT partial turn after inserting it in the socket,the lug will be carried into the inner member of the slot where it willbe prevented from outward movement unt-il turned to the proper position.The plows of the rabble arms are so connected that the resistanceofiered by the ore during the travel of these arms over the variousshelves, is such that there is a tendency to impart rotary movement tothe arms, whereby the lugs upon their inner extremities are held in thelocked position when the shaft is in motion.

IIaving briefly outlined my improved construction, I will proceed todescribe the same in detail, reference being made to the accompanyingdrawing in which is illustrated an embodiment thereof.

In this drawing: Figure l is a vertical section taken through a roastingfurnace, equipped with my improvement. Fig. 2 is a fragmentary sectionalview showing the hollow shaft, one of the hubs with which it isequipped, together with a rabble arm. Fig. 3 is an elevation looking inthe direction of arrow 3, Fig. 2. Fig. 4 is a horizontal section takenon the line 4 4, Fig. 3. Fig. 5 is a vertical section taken on the line5-5, Fig. 4. Fig. 6 is a cross section of one of the rabble arms takenon the line 6 6, Fig. 2. Fig. 7 is a fragmentary elevation of one of therabble arms looking in the direction of arrow 7, Fig. 6. Fig. 8 is adetail view showing one of the rabble arm plows. Fig. 9 is a fragmentaryunderneath view of one of the rabble arms. Fig. l0 is a similar viewshowing the plows in a different position.

The same reference characters indicate the same parts in all the views.

Let the numeral 5 designate a cylindrical casing equipped with shelves 6which separate the roasting chamber into compartments 7, S, 9, 10, 11and 12, the said compartments 5 being numbered from the top downwardly.These shelves are stationary, t-he uppermost shelf having a centralopening 13 surrounding a hollow rotary shaft 14. The shelf next below isequipped with openings 15 at its outer edge, while the next shelf isequipped at its inner edge with an opening 1G, and so on, until thebottom of the furnace is reached. The ore is discharged in the roastedcondition from the bottom compartment 12 through a spout 17.

The shaft 14 is hollow and open at both ends to allow the air tocirculate freely therethrough for cooling purposes. The inner edge ofthe top 13 of thel casing is provided with a collar 19 whose lowerpor-tion extends into the compartment 7 and has an angular grooveadapted to receive a iiange d20, forming a tight joint to prevent thepossible escape of the fumes around the shaft.

The upper portion of the roaster above the top 13 is filled with asuitable packing material 20A which insulates the furnace, so to speak,and aids in maintaining the necessary degree of heat for roastingpurposes.

iseach hub Q1 is substantially the same as every other hub of the rotaryshaft 14,

the description of one of these hubs will be sufficient for all. Eachhub is composed of two substantially twin members 22 which are connectedtogether by locking plates 23 located in recesses Q4 formed in themembers 22 and registering with each other when the two members areplaced together. Before bringing the two members together the plates 23are inserted in the recesses 24 of one member, after which the othermember is applied, the protruding portions of the plates Q3 entering therecesses of the companion member. W'hen this is done, wedge-shapedlocking keys 25 are inserted in vertical openings 26 formed in themembers Q2 and ex tending through the same and intersecting the recesses24, the plates 23 being also apertured to receive the locking keys 25.By

virtue of this construction, the members 22 are locked securely in placeupon the shaft, the latter being equipped with supporting collars 27upon which the hubs rest..

Each hub, as illustrated in the drawing,

is equipped with a number of sockets 28 adapted to receive the innercone-shaped extremities 29 of the rabble arms 30. The body portions ofthese rabble arms are cylindrical, as illustrated in the drawing, whileltheir inner extremities are tapered to lit the sockets of the hubs. Eachhub is provided with a slot or groove 3l which extends into the hub ashort distance, and terminates in a oove 3Q. extending at right anglesto the groove 31 and adapted to receive a lug 33 which is shaped toenter the slot 31, after which the arm is given a partial turn, causingthe lug 33 to enter the locking portion 32 of the slot, forming a sortof bayonet joint connection between the hub and the rabble arms.

As shown in the drawing, each rabble arm 30 is provided with a series ofpins or lugs 34, adapted to enter perforations 35 formed in the upperextremities of curved members 36 arranged to partially surround therabble arms.v By referring to Fig. 6 of the drawing', it will beunderstood that as these arms travel in the direction of the arrow A ofsaid figure, the force acting upon the plows 37 has a tendency to imparta partial rotary movement to the rabble arms, whereby the plows are heldsecurely in place upon the rabble arms, and the latter securely lockedupon the hubs of the various shafts. Each rabble arm is further providedwit-h relatively small pins 38 adapted to enter small recesses 3 9 alsoformed in the curved members 36, thus locking the plows upon the rabblearms whereby they are secured in lace.

llt will be understood from an inspection of the drawing, that Awhilethe plows are locked in place upon the rabble arms when the latter arein motion for ore-roasting purposes, these plows are readily removablefrom the arms by lifting thereon and to this end each curved spannermember' of the plow is provided with a lug 4() having a perforation 41adapted to receive a tool (not shown), which may be inserted into thefurnace for the purpose of lifting the plows from the rabble arms whenfor any reason it may be necessary so to do.

The lower extremity of the hollow shaft 14 is connected by means ofseparated webs 42 with vthe upper extremity of a sha-ft 43 secured tothe hub 44 of a bevel gear 45 mounted upon a stationary support 46. Thegear 45 meshes with an operating pinion 47 mounted on a shaft 49, oneextremity of which is journaled in a bearing 50 formed integral with thebase 46. The outer extremity of the shaft 49 is journaled in a dependingbearing 51. Connected with the outer' extremity of this shaft is apulley 52 which may be connected with any desired power for operatingpurposes.

When the roaster is in operation, the material to be treated is fed tothe upper shelf of the roaster through a conduit 53 whose lowerextremity enters an opening 54 in the top 1S of the structure.Communicating with the uppermost compartment 7 of the structure is apipe 55 for carrying ofi:l the fumes and delivering them to a smokestack (not shown). rlhe combustible material, as sulfur, contained inthe ore is ignited as the material is discharged into the furnace, anysuitable provision being made for this purpose. The shaft 14, carryingthe rabble arms, is rotated whereby the said arms are made to travelaround in their respective compartments, the plows of the arms actingupon the ore to cause the same to travel in a zigzag course through thefurnace from top to bottom. For instance, the ore in the uppermostcompartment is gradually worked toward the center by the action of theplows carried by the rabble arms whereby it is discharged through thecentral opening 18 to the compartment lS next below. In this last namedcompartment, the plows of the rabble arms are so arranged that the oreis caused to travel outwardly upon the shelf and gradually passdownwardly through openings 15 at the outer edge of the shelf or hearth,and thence int-o the compartment 9. From this last named compartment. itis discharged through a central opening 16 into the compartment 10, andso on, until it reaches the lowermost compartment 12 of the furnace,whence it is carried out of the furnace through a discharge pipe 17completely roasted. In order to cause the ore to travel in oppositedirections upon the dierent hearths or shelves during the operation oft-he apparatus, the rabble arms are equipped with suitable plows. Thedistinction between the plows upon the two arms is illustrated in Figs.9 and 10. In Fig. 9 the plows being shown straight with the spanner armswhich support them, while in Fig. 10 the plows are set at an angle tothe arms whereby the material is caused to travel in the desireddirection. As shown in the drawing the plow members or the lowerextremities of the plows are formed integral with the Spanner arms andShanks. In this event the devices are cast or constructed with the plowmembers differently arranged with reference to the spanner arms, and theVrabble arms are equipped with plows of such construction as to give thedesired result in the handling of the ore upon the various hearths ofthe furnace. In Fig. 1 of the drawing no attempt has been made to showthe plows occupying dierent positions, owing to the small scale of thedrawing in this view.

The peculiar shape of the lower extremity 37A of each plow is worthy ofmention. This portion, or the plow proper, occupies an inclinedposition, its forward extremity being lowermost, while the plow isupwardly inclined therefrom. By virtue of this construct-ion the plowhas a tendency to lift the ore as it passes therethrough since the oreis compelled to travel upwardly from the point of the plow until itescapes or leaves the rear end thereof. This is important since itmaintains the ore to be roasted in a loose condition, whereby it may bemore advantageously acted upon by the heat whose function is the burningout of the sulfur and other impurities which when in a raw state renderthe ore refractory or difficult to treat, as heretofore explained.

It will be understood that the hubs 21 must be locked to rotate with theshaft 14. As shown in the drawing this is accomplished by formingrecesses 56 in the collar 27 of the shaft, adapted to receive dependinglugs or teeth 57 formed on the hub. It is evident that several sets oflocking ydevices of this character may be provided for locking each hubupon the shaft to rotate therewith. By virtue of this construction thehubs are securely locked upon the shaft and at the same time are readilydetachable as will be undertsood from the foregoing explanation.

Having thus described my invention what I claim is:

1. In a roasting furnace, t-he combination with a rotatable hollowshaft, of rabble arms connected with the said shaft which is equippedwith exterior hubs having tapering sockets to receive the innerextremities of the arms the said sockets terminating' outside of thehollow of the shaft, the arms having lugs adapted to enter angle-shapedslots formed in the hub, and plows connected with the rabble arms andhaving a tendency to impart rotary movement to the said arms, wherebythe lugs of the arms are held in the locked relation with the hub, forthe purpose set forth.

2. In a roasting furnace, comprising a casing, an upright rotatablehollow shaft equipped with exterior hubs having sockets terminating onthe outside of the hollow of the shaft, rabble arms whose innerextremities are adapted to enter the sockets of the hubs, the latterhaving angle slots and the rabble arms lugs to engage said slots ininterlocking relation, and plows mounted on the rabble arms and arrangedto exert a rotative force upon the rabble arms whereby the latter areheld securely lockedyin the hubs during the rotation of the shaft.

3. A roasting furnace, comprising a chamber, a centrally located uprighthollow shaft equipped with rabblearms, the shaft having exterior hubsprovided with tapering sockets terminating on t-he outside of the hollowof the shaft, the said hubs having angle-shaped grooves formed in thewalls of the sockets, the inner extremities of the rabble arms beingequipped with lugs to enter said grooves, and plows arranged upon therabble arms to impart a rotative force upon the said arms whereby thelatter are held in operative relation with the hubs during the rotationof the shaft.

4. A roasting furnace provided with a vertically arranged rotatablehollow shaft, equipped with exterior hubs having sockets terminating onthe outside of the hollow of the shaft, grooves formed in the sockets,

each groove having an inwardly directed straight portion and a portionextendingl at right angles to the straight portion, and rabble armswhose inner extremities are adapted to enter the said sockets andequipped with lugs adapted to enter the angle-grooves of the sockets,the inner iportion ot' each groove extendingl rearwardly with referenceto the travel of the rabble arnis whereby the resistance otl'ered tosuch travel by the ore imparts a rotatative force to the rabble arms,whereby their lugs are caused to engage the inwardly located andrearwardly directed grooved portions of the hubs, substantially asdescribed.

ln apparatus of the class described, the combination ot a verticallyarranged hollow shaft lmounted to rotate, an exterior hub mounted on theshaft and having` sockets terminating on the outside of the hollow ofthe shaft and equipped with grooves having portions extending` inwardlyfrom the outer extremities of the sockets and interior portionsextending at an angle to the first named portions, and rabble armshaving extremities adapted to enter the sockets and equipped with lugsadapted to enter the grooves ot' the hub, the interior portions of thesaicL Orooves extending rearwardly with reference to the travel of therabble arnis whereby a rotative force is imparted to the said arms,substantially as described.

6. An upright hollow shaft equipped with exterior hubs arranged oneabove another, each hub consisting of two members recessed to receiveinterlockingl apertured plates, the hub members having aperturescommunicating with the plate apertures, and wedgeshaped keys inserted inthe apertures of the hubs and plates for interlocking purposes, the saidhubs also having,` sockets terminating on the outside of the hollow ofthe shaft, and rabble arins adapted to enter the said sockets,substantially as described.

7. A roasting furnace equipped with a vertical hollow shaft providedwith exterior hubs arranged one above another, each hub having a socketterminating on the outside of the hollow of the shaft and provided withan angle groove. formed in its wall, the said groeve extending inwardlyfrom the extremity of the socket and having' an interior member at anangle to the first named member, and a rabble` arm having a lug,-adapted to enter the groove of the socket, the shaft being` mounted torotate, and the interior groove member of the hub being rearwardlydirected with reference to the travel of the rabble arm, for the purposeset forth.

ln testimony whereof I aix my signature in presence of two witnesses.

CHAUNCEY E. DFWEY V'Vitnesses z ELIZABETH BOWEN, A. EBERT GBRIEN.

Copies of this patent may be obtained for ve cents each, by addressingthe Commissioner of Patents, Washington, D. C.

